Significant amounts of ferrous and non-ferrous metal scrap are produced in manufacturing plants with a variety of machining operations. Scrap produced in such plants can include small, non-uniform fragments and sometimes powder. Such scrap is suitable for remelting in a furnace such as a cupola furnace, but since some of the particles of scrap introduced into such a furnace are in finely divided form, the hot gases rushing through the furnace may entrain such particles and carry them to the atmosphere. Thus, particles may not only be lost to the melt, but may contribute to atmospheric pollution.
For over a century, it has been recognized that a solution to the scrap reuse problem lay in introducing the scrap particles to the furnace in a form which would permit the particles to sink into the melt rather than to be entrained in the rising gases. Thus, U.S. Pat. No. Re. 2,250, dated May 22, 1866, describes and claims a process whereby scrap particles are mixed with earth, clay or similar material to which is added water or sulphuric acid in order to aggregate the scrap to pieces large enough to fall into the melt upon being introduced to an operating furnace. U.S. Pat. No. 132,743, dated Nov. 5, 1872, describes the packing of scrap material into wooden boxes, instead of the then used cast iron vessels, and charging the boxes to a furnace. U.S. Pat. No. 3,864,092 which issued Feb. 4, 1975, discloses forming scrap metal particles with a binder into blocks having openings therethrough and the introduction of such blocks to a furnace.
Consideration has also been given to wrapping the scrap in conventional cardboard or paper materials. However, such materials burn quickly in the intense heat of a furnace and thus release the scrap in a region wherein it may become entrained in the gas flow.
While aggregation or agglomeration of the scrap particles with a non-metallic material or enclosure of the particles within a strong container both offer a solution to the scrap loss problem, they provide a relatively expensive solution. The present invention is aimed at enclosing the scrap particles in a relatively weak container which minimizes losses as effectively as the strong container, yet simplifies and reduces the handling costs of containerization.